Final answer:
In Shakespeare's 'Othello,' Othello trusts Cassio to be in charge of Desdemona when he must leave after their marriage, which becomes a pivotal point for Iago's scheming.
Step-by-step explanation:
In William Shakespeare's play Othello, when Othello must leave shortly after his marriage to Desdemona, he leaves Cassio in charge of his wife in the meantime. Othello trusts Cassio and sees him as a loyal lieutenant; thus, he asks Cassio to ensure Desdemona's safe transport to Cyprus. The situation is significant since it sets the stage for Iago's manipulative schemes, which rely on his ability to create suspicion around Desdemona and Cassio's relationship.